Sheet metal joint



Oct. 28,1969

G. B. FOSTER SHEET METAL JOINT Filed June 27, 1968 w 14 6 3 w a N O l m f I N VENTOR. GLEN B. FOSTER United States Patent O 3,474,585 SHEET METAL JOINT Glen B. Foster, Rte. 3, Box 99, Daphne Trailer Park, Michigan City, Ind. 46360 Filed June 27, 1968, Ser. No. 740,696 Int. Cl. E04b 1/54; E04d 3/16 US. Cl. 52394 3 Claims ABSTRACT OF THE DISCLOSURE A joint connecting first and second sections or panels of sheet metal wherein each sheet includes a marginal portion having multiple return folds. The multiple return folds of said first and second panels of sheet metal are interlocked to form a tight sealed flat joint.

BACKGROUND OF THE INVENTION In constructing housing units, such as mobile homes and travel trailers, panels or sections of sheet metal roofing and siding must be joined in a rapid, economical seal forming manner. One customary means of joining such panels of sheet material is through the use of a capped joint as shown in US. Patent 3,213,583. In a joint of this type, the marginal portions of the joined panels each include a return bent flange over which a cap is applied and clamped. Not only do joints of this type require the use of a separate capping or joint component which makes the joint diflicult to assemble and of high cost, but there is a tendency for such joints to loosen when the trailer is subjected to road shock during travel. Another means heretofore used in joining panels of sheet metal is shown in US. Patent 451,550. In this type joint a corrugated terminal flange extends laterally from the innermost interlocking marginal portion of the joint. This corrugated flange adds to the amount of material required to eflect the joint seal and thereby increases its unit cost.

SUMMARY OF THE INVENTION This invention concerns a joint for connecting first and second panels or sections of sheet metal having interlocking marginal portions. The marginal portion of the first panel includes multiple return folds defining upper, middle and lower runs. The lower and middle runs of the first panel are connected by an arcuate bend and have portions in face engagement. The upper and middle runs of the first panel are spaced apart, with the upper run extending laterally beyond the bend between said lower and middle runs and terminating in a downward return bent spaced flange. The marginal edge of the second panel also includes multiple return bentfolds defining upper, middle and lower runs. The lower and middle runs of the second panel are spaced apart and receive therebetween the terminal flange of the first panel. The upper and middle runs of the second panel are in face engagement and have portions thereof disposed between the upper run and the terminal flange of the first panel. The upper run of the second panel extends substantially the full width of the upper run of the first panel and terminates in a downward return bent flange. The terminal flange and upper run of the second panel have face engaging portions disposed between the upper and middle runs of the first panel. The end edge of the terminal flange of the second panel terminates spaced from the bend of the first panel.

As an alternative embodiment, the joint above described may be modified so that a part of the upper run of the second panel which extends laterally beyond the bend joining the lower and middle runs of the second panel includes a longitudinal channel portion which extends downwardly between the bends joining the lower and middle runs of said first and second panels. An elongated seal means is disposed within said channel portion and engages in sealing contact the upper run of the first panel.

The joint of this invention is of two piece construction utilizing a minimum amount of sheet metal to form a rigid interlocking seal. The joint is so designed that all exposed bends of the interlocking sheet metal panels, that is, the two bends exposed at the sides of the joint, are of such a radius that neither the base sheet nor the galvanizing, if any, is cracked or broken about the exposed radii of the bends.

Accordingly, it is an object of this invention to provide a sheet metal joint of economical tightly sealed construction.

It is a further object of this invention to provide a rigid sheet metal joint having interlocking portions which form a tight seal and are not susceptible to lossening by shock and vibration of the joined sheet metal panels.

It is still another object of this invention to provide a sheet metal joint having all exposed bends of an arcuate configuration so as to preclude cracking or breaking of the base sheet metal and galvanizing, if any, at said bends during fabrication.

Other objects of this invention will become apparent upon a reading of the inventions description.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary perspective view of two sections of sheet material joined in accordance with the teachings of this invention.

FIG. 2 is an end view of the joint shown in FIG. 1 prior to crimping thereof.

FIG. 3 is a cross sectional view of a finished joint taken along line 33 of FIG. 1.

FIG. 4 is an end view of an uncrimped joint of modified form.

FIG. 5 is a cross sectional view of the joint of FIG. 4 in crimped form.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments illustrated are not intended to be exhaustive or to limit the invention to the precise forms disclosed. They are chosen and described in order to best explain the principles of the invention and their application and practical use to thereby enable others skilled in the art to best utilize the invention.

The embodiment illustrated by FIGS. 1 and 3 consists of two panels or sections 10 and 12 of sheet metal, which may consist of galvanized rolled steel. Panel 10 has its marginal portion 14 bent along multiple parallel return folds to define an upper run 16, a middle run 18 and a lower run 20. Lower run 20 and middle run 18 are connected by an arcuate bend 22 of small radius and have portions thereof in face engagement. The upper run 16 and middle run 18 of panel 10 are spaced apart and connected by a bend 24 of larger radius than bend 22. Upper run 16 is of greater width than middle run 18 and extends laterally beyond the arcuate bend 22 of panel 10 and terminates in a downwardly return bent flange 26 spaced below said upper run.

The marginal portion 28 of sheet metal panel 12 is bent along multiple parallel return folds to define an upper run 30, a middle run 32 and a lower run 34. Lower run 34 and middle run 32 of panel 12 are spaced apart and connected by a bend 36. The terminal flange 26 of panel 10 is received between lower run 34 and middle run 32 of panel 12. The upper run 30 and middle run 32 of panel 12 are in face engagement and have portions thereof disposed between the upper run 16 and the terminal flange 26 of panel 10. The upper run 30 of panel 12 is wider than the middle run 32 and extends laterally beyond bend 36 for substantially the full width of the bottom face of the upper run 16 of panel 10 and terminates in a downward return :bent flange 38. The terminal flange 38 is in face engagement with the upper run 30 of panel 12 and these parts are disposed between the upper run 16 and the middle run 18 of panel 10. The edge 40 of terminal flange 38 of panel 12 terminates spaced from bend 22 of panel 10 as shown in FIGS. 1 and 3.

To construct the joint illustrated in FIGS. 1 and 3, the marginal portions 14 and 28 of panels 10 and 12 are formed into opposed hook-shaped parts 42 and 44 and engaged as shown in FIG. 2. Edge 40 of panel 12 terminates spaced from the plane of upstanding web 43 of hook-shaped part 42. The assembled marginal portions are then rolled and crimped by suitable means to form the flattened joint illustrated in FIGS. 1 and 3.

The embodiment illustrated in FIG. is a modified construction of the joint shown in FIGS. 1 and 3. The upper run 30 of panel 12 includes a depending channel portion 46, defined by sides 48 and interconnecting web 50, which projects between bends 22 and 36 of panels and 12 respectively, as shown in FIG. 5. The spacing between the bottom side 31 of the upper run 30 of panel 12 and the outer face 51 of web 50 of channel portion 46 is preferably slightly greater than the combined thickness of the terminal flange 38 of panel 12 and the lower and middle runs 20, 18 of panel 10. A seal member 52, which may be formed of a rubber or plastic composition, is disposed longitudinally within channel portion 46 and projects at least slightly above the top surface of upper run 30. Seal member 52 is preferably placed in compression during forming of the joint and engages the inner face of web 50 of channel portion 46 and upper run 16 of panel 10.

To construct the joint illustrated in FIG. 5, the marginal portions 14 and 28 of panels 10 and 12 are formed into opposed hook-shaped parts 42 and 44'. Seal member 52 is laid in channel portion 46 of part 44' and part 42 is applied over part 44'. End edge 40' of part 44' may terminate adjacent upstanding web 43 of part 42. The assembled marginal portions are then rolled and crimped to form the joint illustrated in FIG. 5.

What I claim is:

1. A joint connecting first and second panels of sheet metal, said panels having interlocking marginal portions, the marginal portion of said first panel having multiple return folds defining upper, middle and lower runs, said lower and middle runs being connected by an arcuate .bend and having portions in face engagement, said upper and middle runs being spaced apart, said upper run being wider than said middle run and extending laterally beyond said arcuate bend and terminating in a downward return bent flange spaced therefrom, the marignal portion of said second panel having multiple return bent folds defining upper, middle and lower runs, thelower and middle runs of said second panel being spaced and receiving therebetween the terminal flange of said first panel, the upper and middle runs of said second panel being in face engagement and having portions thereof disposed between the upper run and the terminal flange of said first panel, the upper run of said second panel extending substantially the full width of the bottom face of the upper run of said first panel and terminating in a downward return bent flange, the terminal flange and upper run of said second panel having face engaging portions disposed between the upper and middle runs of said first panel, and the edge of the terminal flange of said second panel terminating spaced from said arcuate bend of said first panel.

2. The joint of claim 1, wherein the upper run of said second panel is wider than the middle run of said second panel and has a longitudinal channel portion extending downwardly between the bends joining the lower and middle runs of respective first and second panels, and an elongated seal member seated in said channel portion and engaging the bottom of the upper run of said first panel.

3. A joint connecting first and second sheet metal panels, said panels having interlocking marginal portions, the marginal portion of said first panel having multiple return folds defining upper, middle and lower runs, said lower and middle runs having portions in face engagement, said upper and middle runs being spaced apart, said upper run being wider than said middle run and terminating in a downward return bent spaced flange, the marginal portion of said second panel having multiple return bent folds defining upper, middle and lower runs, the lower and middle runs of said second panel being spaced and receiving therebetween the terminal flange of said first panel, the upper and middle runs of said second panel having face engaging portions disposed between the upper run and terminal flange of said first panel, the upper run of said second panel extending laterally beyond the middle run of said second panel and including a longitudinal channel portion extending downwardly between the bends joining the lower and middle runs of respective first and second panels and terminating in a downward return bent flange, an elongated seal member received within said channel portion and engaging the bottom of the upper run of said first panel, and the terminal flange and upper run of said second panel having face engaging portions disposed between the upper and middle runs of said first panel.

References Cited UNITED STATES PATENTS 425,104 4/ 1890 Mallory 52520 451,550 5/1891 Bayer 52528 3,213,583 10/ 1965 Winski 52395 3,312,028 4/ 1967 Schroyer 52-520 X FOREIGN PATENTS 1,032,997 6/ 1966 Great Britain.

ALFRED C. PERHAM, Primary Examiner U.S. Cl. X.R. 52-528, 748 

